Part A. To find the growth factor of the town, you can proceed like this

So, the growth factor for the town will be

For part B, exponential growth is modeled by the equation

So, you have

For part C, you need to find the population in 2011, so

Then, plug in the equation found x = 5

Therefore, the population of Tewksbury in 2011 will be 27874 people.